GOST 29001-1991 Inductor and transformer cores for telecommunication. Part 3. Blank detail specification magnetic oxide cores for broad-band transformers assessment levels A and B
GOST 28900-1991 Guide to the specifications of limiting values for physical imperfections of parts of ferromagnetic oxides
GOST 28997-1991 Inductor and transformer cores for telecommunication. Part 1. Generic specification
GOST 29000-1991 Inductor and transformer cores for telecommunication. Part 3. Sectional specification magnetic oxide cores for broad-band transformers
GOST 29001-1991 history
1991GOST 29001-1991 Inductor and transformer cores for telecommunication. Part 3. Blank detail specification magnetic oxide cores for broad-band transformers assessment levels A and B